1. Field of the Invention
The present invention generally relates to a flat panel display device that is light, slim, flexible, and portable. Particularly, the present invention relates to an application of electrophoretic display (EPD) technology in an electrophoretic display structure of electronic paper displays.
2. Description of the Related Art
Not only are Electronic-books (E-books) advantageous in simultaneously possessing display qualities of conventional paper as well as possessing the property of being mechanical and flexible in nature, Electronic-books (E-books) are also further advantageous for having integrated the real-time updating characteristic of digital electronic medias. Consequently, electronic paper displays are gradually becoming more commonly accepted by the consumer and are at the forefront in replacing conventional paper in the near future.
FIG. 1 is a schematic diagram of the conventional electrophoretic display structure utilizing electrophoretic display technologies. The conventional electrophoretic display structure includes a substrate 10, an electrophoretic display layer 30, a protective layer 40, and an edge sealant 50. As shown in FIG. 1, the electrophoretic display layer 30 further includes a waterproof layer 20 and a plurality of electrophoretic display elements 35 and is then connected to an activation layer 15 and the substrate 10. The electrophoretic display layer 30 is driven by the activation layer 15 to force the electrically charged electrophoretic display elements 35 to change positions in order to exhibit the contrast between the elements and the substrate 10 or the contrast of the color differences between the elements themselves. In turn, the contrast forms a pixelated image for displaying purposes. Within the boundaries of the edge sealant 50 surrounding the exterior of the electrophoretic display layer 30, a gap 25 exists between the activation layer 15 and the protective layer 40. The gap 25 may be used for sealants for filling or padding purposes.
In terms of the edge sealant 50 with low viscosity, the conventional electrophoretic display structure is customarily lacking in waterproofing abilities as water vapor can easily infiltrate the electrophoretic display layer 30 during the quality assurance or assembling stage, resulting in abnormal activation operation of the electrophoretic display elements 35. On the other hand, if the edge sealant 50 has high viscosity, the gap 25 cannot be easily filled. After the curing process, any gas that was left behind in the gap 25 would have expanded out of the plastic frame 50 and left formations of bubbles or holes.